Unit 1 The Plant Body

Question 1

What consists of the angiosperm plant body?

Answer 1

1) Root System

2) Shoot System

Question 2

What is part of the root system?

Answer 2

• Structures usually belowground

- main and lateral roots and root hairs

Question 3

What is part of the shoot system?

Answer 3

• Structures aboveground

- stems, leaves and flowers

Question 4

How to identify leaves, stems and roots?

Answer 4

1) The external appearance and location of the organ can be used
2) The arrangement of vascular tissue varies within the three organs
3) Vascular tissue is also different in monocots and dicots

Question 5

Shoot System

Answer 5

• Stem and leaves
• More complex than the root
• Has nodes and internodes with one or more leaves at each node
• Strands at the vascular cylinder of the stem turn outward and extend into the leaf, leaving gaps opposite the leaf

Question 6

What is the function of the stem?

Answer 6

Supports and displays the leaves to capture sunlight

-Conduction of sugars through the phloem and water in the xylem

Question 7

Growth of Stem

Answer 7

In length occurs by internodal elongation

-Have stomata but fewer than in leaves

Question 8

What is the shoot apical meristem?

Answer 8

Has no protective covering, though young leaves fold over it

Question 9

Primordia

Answer 9

Leaf–>develop into leaves

Bud–>develop into lateral shoots

Question 10

What are the stem tissue systems?

Answer 10

1) Dermal
2) Ground
3) Vascular

Question 11

Dermal

Answer 11

Epidermis

Question 12

Ground

Answer 12

Cortex and pith

Question 13

Vascular

Answer 13

Vascular bundles with phloem and xylem

Question 14

Discrete vascular bundles

Answer 14

Vascular bundles form a single ring around the pith

Question 15

Scattered vascular bundles

Answer 15

Scattered through the ground tissue

Question 16

How do leaves vary?

Answer 16

Variation in leaf structure is often related to the habitat or environment

Question 17

What is the function of the leaf?

Answer 17

Photosynthesis

Question 18

How does photosynthesis works in a leaf?

Answer 18

A flat blade exposes a large surface area to absorb sunlight for the light reactions of photosynthesis

• Gas exchange (water and carbon dioxide) occurs through the stomates
• Veins transport (collect) the products of photosynthesis

Question 19

Phyllotaxy

Answer 19

Pattern of leaf arrangement on the stem

Question 20

Types of Phyllotaxy

Answer 20

1) Spiral (most common type)
2) Opposite (pairs at each node)
3) Whorled (3 or more leaves at each node)

Question 21

Blade (leaf)

Answer 21

lamina, expanded portion

Question 22

Petiole (leaf)

Answer 22

stalk portion

-connects the leaf to the stalk

Question 23

Sessile leaf

Answer 23

lacks a petiole

Question 24

Leaf sheath

Answer 24

the base of the leaf that encircles the stem; common in grasses and other monocots

Question 25

Dermal Tissue System (leaf)

Answer 25

Leaf epidermis is usually a single layer of cells covered with a waxy cuticle with stomates embedded in this layer on the upper and lower surface
-includes hairs or trichomes

Question 26

Parts of the Ground Tissue System (leaf)

Answer 26

1) Mesophyll
2) Palisade Parenchyma
3) Spongy Parenchyma
- for both types of parenchyma, distinction is typically not labeled with monocots

Question 27

Mesophyll

Answer 27

Specialized cells for photosynthesis

Question 28

Palisade Parenchyma

Answer 28

Columnar cells on the upper surface and have more chloroplasts and perform more photosynthesis

Question 29

Spongy Parenchyma

Answer 29

Irregular cells on the lower surface, less photosynthesis

Question 30

Vascular bundles

Answer 30

Veins are continuous with the vascular system of the stem

-Veins contain xylem and phloem

Question 31

Function of the veins

Answer 31

Major veins–> transports photosynthesis out of the leaf

Minor veins–> collects carbohydrates from the mesophyll

Question 32

Leave types

Answer 32

Monocot (parallel veins)

Dicot ( branching or netted veins)

Question 33

Types of Leaves in the Environment

Answer 33

1) Mesophyte
2) Hydrophyte
3) Xerophyte
4) Sun and Shade leaves

Question 34

Mesophyte

Answer 34

Grows in environments that are neither too wet nor too dry

-small, few air spaces

Question 35

Hydrophyte

Answer 35

Grows submerged or requires a large supply of water

• stomata are on the upper surface
• large air spaces, help floats

Question 36

Xerophyte

Answer 36

Adapted to arid habitats

• May have thicker cuticle and multiple layers of epidermis
• Stomata are sunken in depressions on the lower surface
• Trichomes may also retard water loss

Question 37

Sun and Shade Leaves

Answer 37

Leaves that develop in high light are smaller in area and thicker with more layers of palisade parenchyma